1. Development and design of a wall climbing robot

2. Development and design of a wall climbing robot
Project by
Jithin George A4PS 291H
Jaideep Singh Chavan B5A4 412H
Sarthak Ghosh A3PS 211H

3. Objective : To be able to traverse a vertical perpendicular wall
To remain stationary on a vertical perpendicular wall

4. The final design selected
The flipping robot

5. The suction mechanism

6. Locomotion Mechanism

7. Final product

8. New mechanism for turnning

9. Control of the robot S R X Y
Let R and S represent the signals used to represent the rotation of the 2 motors used for the shaft movement.
Let X and Y represent the signals used for the motors controlling the piston movement

10. State diagram S0 (Idle) On/0011 S1 S3 Counter/0011 On,Counter/1101

11. R S X Y
0 0 1’ 1
Pistons moved up
X piston moves down, Y still up
R and S both rotate and Y is still up
X and Y pistons are moved up

12. R S Y X
Exchange the signals of X and Y , R and S.
We go back to the start.

13. Integrating the turning possibility
S0(Idle)
On/0011
T=0/1101 S1 S3
Counter/0011
T=1/Turn=1 and 1101
On,counter/001’1
T=0/1101 S2
On,Counter/1101 S4

14. Detecting Adjacent Walls
Assumptions: Most walls adjacent to vertical walls (the ceiling) are almost always at 90 degree to the vertical wall.
Use of proximity sensor to detect a right angled wall which is sufficiently close.

15. Proximity Sensor
A proximity sensor often emits an electromagnetic field or a beam of
electromagnetic radiation (infrared, for instance), and looks for
changes in the field or return signal.

16. Infrared Proximity Sensor

17. Detection of Right Angled Walls
Let Motor X is fixed to the Wall and Let Motor Y be free.
Thus Motor X is responsible for the rotation of the arm and Motor Y is responsible for the rotation of the suction cup at the other end.
We rotate Motor Y at a speed double of Motor X.
By the time Motor X completes 90 degree, suction cup has rotated 180.

18. Detection of Right Angled Walls
So the current situation is this : X Y
Now we stop the motor X and start polling the proximity sensors to see if the wall at front is lesser than L distance away.
If not we carry on regularly, otherwise we align the suction cup Y.

19. Detection of Right Angled Walls
So the next desired snapshot can be :
Regular motion
Desired Motion

20. Detection Of Right Angled Walls
After the detection of the wall takes place, for every degree anticlockwise rotation of the motor X, Motor Y rotates equally in an anti-clockwise direction.
This ensures that attaching surface of the cup remains parallel to the perpendicular wall.

21. Obtuse Angled Walls
Start polling the sensor when the arm is at 90 degree to the current wall.
Do not rotate the motor handling the suction cup until a wall is detected.
Detect the adjacent wall which is close enough
Stop the motor that is fixed to the current wall
Rotate the suction cup till both the sensors attached to it start giving equal values.
Once equal values are returned, for every degree rotation of the motor fixed to the wall, the motor handling the suction cup rotates the same amount in the opposite direction. This ensures that the relative orientation is maintained.
Repeat step 6 until the cup holds on to the adjacent wall.

22. Obtuse Angled Walls Aligns by checking if both sensor values are same.
Detects wall in this position

23. State Diagram with Right angled wall detection
S0(Idl e)
T=0/1101
On/0011
T=1/Turn=1 and 1101 S3 S4 S1
W=0,Counter/0011
T=0/1101
On,counter/001’1
W=1/11’01
On,Counter/1101 S2 S5
W=0/0011

24. Problems with fabrication
Lack of concise and cheap motors.
Material required couldn’t be found and used easily.
Time constraint

25. Conclusion
We have designed our own unique wall-climbing robot with mechanisms for suction, rotation and turning. We implemented techniques for its control as well.
In future, we believe we can fabricate this efficient prototype.

26. Thank you!